[V0 Deprecation] add clear messages for deprecated models

[youkaichao]

The model was deprecated in #21217 . Let's leave a clear error message and guide users to use which versions.

[github-actions]

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[gemini-code-assist]

Code Review

This pull request aims to provide clearer error messages for deprecated models by introducing a dedicated check. The implementation correctly identifies when a deprecated model is being used. However, there is a critical bug in how the deprecated model's information is retrieved, which could lead to a KeyError and crash the application under certain conditions. I've provided a code suggestion to fix this issue and make the error message more specific and helpful to the user.

[ywang96]

LGTM but I left a nit

[youkaichao]

the error message will look like:

ValueError: Model architecture Phi3SmallForCausalLM was supported in vLLM until version 0.9.2, and is not supported anymore. Please use an older version of vLLM if you want to use this model architecture.